The most common type of such machines is tiltable disc machines. Many such machines are heavy and relative large. Conventional machines are also expensive and cumbersome to make. One object of the invention is to provide an axial piston machine that has smaller dimensions and lower weight and that can be produced at a lower cost than conventional axial piston machines.
This object is achieved by providing an inner part of the piston machine that has a spherical outer surface and an outer portion that has a corresponding spherical inner surface wherein grooves are defined in the spherical outer surface. Pistons are connected to the outer portion of the rotor and adjustment members are adapted to adjust the tilting angle of the inner part to set the operational volume of the present invention.